When the system has been evacuated, the next step is to carry out a thorough leak test.
The system may then be charged with refrigerant. Irrespective of which method of charging is used, it must be remembered that the compressor is being operated for the first time. It will have been standing for a considerable period, and oil will have drained from cylinders and bearings.
Before attempting to start the compressor the following checks must be made:
1. Ensure that the electrical supply voltage is correct according to the compressor motor nameplate.
2. Check the voltage at the compressor motor terminals.
3. Check the fuse ratings.
4. Set the safety controls and check operation.
5. If the compressor is an open type, turn it over by hand if this is practical to verify free rotation.
At this stage it is also advisable to prepare an equipment log and to record electrical data, control settings, operating pressures and temperatures noted during commissioning, in case of a break in continuity during this procedure and for future reference.